With the development of the next generation optical disc player, e.g. HD DVD (High Definition Digital Versatile Disc), BD (Blu-Ray Disc), the content providers have defined a structure (e.g. Viewer's Wish List defined in HD DVD, Graphics Reference Model defined in BD Read-Only), indicating that when a user is watching a content (video and/or audio), some data content, such as Scenes, PlayLists, or Clips of the content, can be extracted and saved, if the user think the Scenes, PlayLists, or Clips are interesting or important. The extracted data content can be saved on an optical disc (or a DRAM temporarily).
Based on the extracted data content, more and more users enjoy sharing their watching experience with other users, that is to say, sharing the extracted data content with other users.
In the conventional system of sharing a data content between a transmitter used by a user and a receiver used by another user, the transmitter (e.g. optical disc player, mobile phone, PDA) is used to generate a message (such as Multimedia Messages) including the extracted data content, and send the message to the receiver (another optical disc player, mobile phone, PDA).
However, using the conventional system to share the extracted data content between a transmitter and a receiver, causes at least three limitations to occur:                1. Based on protecting copyright: if the transmitter is not authorized by a content provider to extract the data content, the sharing data content process does not work. For example, some Clips of content are usually encrypted on BD-ROM for protecting the copyright of the content.        2. The maximum size of a message may be just 45 KB, which is much smaller than the data content (such as a video), if the transmitter is not authorized to encapsulate the data content, the transmitter cannot generate an adaptive message for sharing the data content with a receiver.        3. Different receivers may have different functional parameters (e.g. screen size, resolution, decoding format, capacity), which may not adapt to the received data content from the transmitter. So when the functional parameters of a receiver are not adaptive to the received data content, the receiver cannot play back the data content very well.        
With the limitations mentioned above, it is difficult to share data content between a transmitter and receiver.